In the last several years, the Internet has grown rapidly beyond servers, desktops and laptops to include handheld devices like PDAs and smart phones. There is now a growing realization that this trend will continue as increasing numbers of even simpler, more constrained devices (sensors, home appliances, personal medical devices) get connected to the Internet. The term “embedded Internet” is often used to refer to the phase in the Internet's evolution when it is invisibly and tightly woven into our daily lives.
Embedded devices with sensing and communication capabilities will enable the application of computing technologies in settings where they are unusual today: device and appliance networking in the home, automated full-time monitoring of patient health, remote diagnostics and control of industrial machinery, habitat monitoring, medical monitoring and emergency response, battlefield management, intelligent irrigation. Many of these applications have strong security requirements, e.g. health information must only be made available to authorized personnel (authentication) and be protected from modification (data integrity) and disclosure (confidentiality) in transit. Even seemingly innocuous data such as temperature and pressure readings may need to be secured. Consider the case of a chemical plant where sensors are used to continuously monitor the reactions used in manufacturing the final product. Without adequate security, an attacker could feed highly abnormal readings into the monitoring system and trigger catastrophic reactions.
Secure Sockets Layer (SSL) also referred to as Transport Layer Security (TLS) is the most popular security protocol on the Internet today. SSL combines public-key cryptography for key-distribution/authentication with symmetric-key cryptography for data encryption and integrity. However, public-key cryptography is widely believed to be beyond the capabilities of embedded devices. This perception is primarily driven by experiments involving RSA, today's dominant public-key cryptosystem.